• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.3
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• pp.288-293
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• 2010

This paper presents to calculate the lethality of missile for the simulation test program and to verify the simulation results. In order to calculate a reliable lethality we need may data and experiments of fuse and warhead, but in reality it is hard to perform a task. Therefore, this paper obtained from the reference paper to analyze the lethality data for the calculation of the lethality. We form the 6 DOF simulation model using the MATLAB/SIMULINK. And formed the autopilot algorithm using the vertical and horizontal acceleration feedback and PNG (Proportional Navigation Guidance) command be used to the guidance algorithm. Finally, we evaluate the results about three cases, front launch, side launch and rear launch to simulate the simulation program, and the target is designed to have a constant speed and direction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.121-125
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• 1974

Polyclads (Stylochus ijimai and Pseudostylochus obscurus) which damage oyster were treated with calcium hypochlorite to determine the TLm concentration. In this experiment the TLm and the extermination density as well as the growth of the oyster after the treatment were checked with following results: The higher the temperature and the longer the period of the treatment is, the lower the TLm is. The greater the concentration of sea water is, the higher TLm is because of the weakened action of calcium hypochlorite. When the oyster is treated by calcium hypochlorite at the oyster farm, its extermination concentration is 2.4-7.1 times higher than that of TLm in fresh water. The growth rate was not affected after the treatment.

• KSBB Journal
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• v.15 no.1
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• pp.106-111
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• 2000

Peach fruit month, smaller tea tortrix, and Melotontha incana are major pests of apple and apple trees throughout the country. In this work, we examined efficacies of entomopathogenic nematodes Steinernema carpocapsae and Steinernema glaseri against these apple pests. Steinernema carpocapsae showed 100% mortality after 24hr against peach fruit moth when it was applied on the larva with the concentration of 80 nematodes per larva, but Steinernema glaseri caused 83.3$\pm$5.8% mortality after 24hr at the concentration of 50 nematodes per larva. In the case of smaller tea tortrix, S. carpocapsae and S. glaseri caused 100%, 43.3$\pm$5.8% at the concentration of 50 nematodes per larva after 48 hr, respectively. However, 5~6 instar of Melotontha incana was not killed by treatments with S. carpocapsae and S.glaseri up to concentration of 200~800 nematodes per larva. The motility of nematodes in a soil increased as both inoculation concentration of nematode per larva and temperature increased. The mortality of G. mellonella by S. carpocapsae was 100% up to 10cm in depth and 56.7$\pm$5.8% at 10~15cm in depth when the temperature was $25^{\circ}C$ and 50 nematodes per larva were used.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.323-323
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• 1994

Allyl alcohol은 간에서 두 단계의 효소 반응을 거쳐 대사되는데, 먼저, alcohol dehydrogenase (ADH)에 의해 독성 활성체인 acrolein으로 바뀌고, 이후 계속하여 aldehyde dehydrogenase (ALDH)에 의해 acrylic acid로 무독화되어 배설된다. Ethanol 역시 간에서 대사되는데 있어 같은 효소들을 공유하므로 allyl alcohol과 경쟁적으로 반응할 것이다. 따라서, 본 실험에서는 ethanol에 의한 대사 효소 경쟁반응에 의해 allyl alcohol 의 간독성이 어떻게 변화하는지를 연구하였다. 우선 ethanol과 allyl alcohol을 동시 투여할 경우 5시간째에 allyl alcohol에 의해 증가된 ALT level을 낮춘다는 보고를 확인하고자 ethanol 2 g/kg과 allyl alcohol 40 mg/kg을 동시투여했으나 오히려 치사율이 증가했고, ethanol을 2시간 전처리한 군에서도 역시 치사율이 증가되고, 간의 glutathione 양은 allyl alcohol 단독 처리군에 비해 현저히 감소되는 양상을 보였다.

• Journal of fish pathology
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• v.17 no.3
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• pp.199-205
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• 2004

Effects of nitrite, ammonia and hydrogen sulfide on survival of the early developmental stages of Fenneropenaeus chinensis were determined under continuous flow-through system. The 96hr-$LC_{50}$ values of mysis stage were 18.4 mg/L, 0.69 mg/L and 13.5 $\mu{g}/L$ for nitrite, ammonia and hydrogen sulfide, respectively; 28.3 mg/L, 1.23 mg/L and 20.7 $\mu{g}/L$ for post larva stage and 39.8 mg/L, 1.73 mg/L and 28.5 $\mu{g}/L$ for juvenile stage, respectively. The Fenneropenaeus chinensis sensitivity for the three pollutants was in the order of hydrogen sulfide>ammonia>nitrite. The mysis/post larva, mysis/juvenile and post larva/juvenile ratios of nitrite, ammonia and hydrogen sulfide toxicity were >1.5, >2.0 and <1.5 times, respectively, and mysis were found to be more sensitive to pollutants than juvenile in all cases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.327-334
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• 1994

This study was undertaken to clarify the effect of killing methods on the morphological and histological changes of plaice, Paralichthys olivaceus muscle at early stage after killing. Killed samples by the three different methods were stored at $5^{\circ}$, and the changes in breaking strength of muscle, morphological observation of myofibrils and histological observation of extracellular spaces through storage were monitored. Samples killed by electrifying in sea water showed the maximum value of breakin strength immediately after killing and then it dropped significantly(p<0.05) until 2.5hrs passed. Breaking strength of samples killed by spiking at the head instantly and dipping in sea water including anesthetic rose steadily over 10hrs and 15hrs after killing, respectively. In myofibrills prepared from dorsal muscles immediately after spiking at the head instantly, A-band, H-band, I-band, and Z-line in sarcomere were clearly distinguishable each other. Due to muscle contraction by electrical stimulation, it was impossible to distinguish H-band from I-band observed in sarcomere immediately after killing for samples killed by electrifying. But, in the cases of samples killed by spiking and dipping, H-band could be observed dimly until 10hrs and 15hrs storage. No extracellular space was observed among muscle cells immediately after spiking at the head instantly. Samples killed by spiking at the head instantly and dipping in sea water including anesthetic showed extracellular spaces among all muscle cells after 15hrs and 25hrs storage, respectively. The other hand, samples killed by electrifying in sea water (110V, 30sec.) showed a few extracellular spaces immediately after killing and then it showed extracellular spaces among all muscle cells after 2.5hrs storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.139-142
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• 1984

Short-term acute toxicity of synthetic detergent(LAS) to larvae of loach, Misgurnus angillicaudatus was examined by static bioassay. The larvae were exposed to 15 different concentration of synthetic detergent for 16, 48, 72, 96 and 120 hours in order to determine median lethal concentration($LC_{50}$). The $100\%$ mortarlity of larvae was showed within 120, 96, 48 and 16 hours for 6, 18, 30 and 38 ppm, respectively. The median lethal concentration values of the larvae were 12.59 ppm for 48 hours, 4.00 ppm for 96 hours and 1.02 ppm for 120 hours. The permissible toxicant concentration of acute toxicity to larvae was $0.37{\sim}0.43$ ppm, and application factor of the synthetec detergent was $0.093{\sim}0.108$. The median lethal time($LT_{50}$) for different concentration also was determined. The $LT_{50}$ of 0.2 ppm was found within 165.1 hours and 2 ppm was 106.2 hours, while the $LT_{50}$ of 8 ppm was 60.3 hours and that of 38 ppm was 23.5 hours.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.178-184
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• 2013

Residual toxicity test to honeybee was conducted to evaluate an indirect effects on honeybee after planting hole application of systemic insecticides which were highly toxic to honeybee (Apis mellifera). In this study, It was applied three application rates in the planting hole by three systemic insecticides, dinotefuran GR, imidacloprid GR and clothianidin GR at planting time of tomato. Residual analysis of foliage was carried out after periodic sampling the foliage and investigated the effects of exposed honeybee on the tomato foliage. The honeybee mortality by dinotefuran residues on the foliage was shown almost 100% at 7 days after treatment and decreased 17 days after treatment. The maximum mortality of honeybee by imidacloprid residues on the foliage was 44 ~ 72%. But the effect of pesticide lasted for 18 days and then decreased. The honeybee mortality by clothianidin residues on the foliage was 100% at 7 days after treatment and decreased 14 days after treatment. A tendency of the honeybee mortality and residue in foliage showed a similar character as time goes by. The residues in tomato foliage decreased gradually after 14 days by vigorous growth of tomatoes and the toxic effect of honeybee was significantly decreased after 21 days in actual usage of the treatment.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.501-504
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• 1998

The role of iron as a possible pathogenic factor in the Infection of V. vulnificus was examined in thins paper The effects of iron and $CCl_4$ on the growth of V. vulnificus in human and rabbit sera were also done. Injection of iron to mice resulted in a lowering of the 50% lethal dose and in a reduction in the time of death postinfection. Serum iron levels were also elevated by damaged livers with infections of $CCl_4$- The inoculum size required to kill these mice was directly correlated with serum iron Irvels. Iron appeared to be the limiting factor In the ability of thins organism to survive or grow in mammalian sera. These results, both in vitro and In vivo, provided strong evidence that iron may play a major role In the pathogenesis of V. vulnificus.

• Journal of Life Science
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• v.30 no.4
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• pp.321-330
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• 2020

The aim of this study was to investigate the effect of copper (II) chloride (CuCl₂) on zebrafish. Zebrafish were exposed to various CuCl₂ concentrations and subjected to different exposure times to determine the median lethal concentration (LC₅₀) values. To evaluate stress responses, we measured whole-body cortisol levels and behavioral parameters using the open field test (OFT) or the novel tank test (NTT). The zebrafish were exposed to CuCl₂ solution at concentrations of 1.5-150 ㎍/l or a vehicle for 1 hr before behavioral tests or sample collection for whole-body cortisol. The LC₅₀ values were 30.3, 25.3, and 14.8 ㎍/l at 24, 48, and 96 hr, respectively. The NTT showed that mobility, velocity, and distance covered were significantly lower in zebrafish exposed to CuCl₂ than in the control group (p<0.05), while the turn angle was significantly higher in zebrafish exposed to a CuCl₂ concentration of 150 ㎍/l than in the control group (p<0.05). The OFT also showed that mobility, velocity, and distance covered were significantly lower and the turn angle and meandering were significantly higher in zebrafish exposed to all concentrations of CuCl₂ than in the control group (p<0.05). The whole-body cortisol levels were significantly higher in zebrafish exposed to CuCl₂ than in the control group (p<0.05). These results suggest that exposure to lethal CuCl₂ concentrations induces an intense toxic and stress response in zebrafish, causing behavioral changes and increasing whole-body cortisol levels.